猪PSE肉与正常肉的肌原纤维形态学比较研究

Comparative Studies on Myofibrillar Morphology in PSE and Normal Porcine Muscle

通过肌原纤维的形态学、易碎度和肌节长度的测定,对猪PSE肉和正常肉肌原纤维的易碎性进行了比较研究,发现肌原纤维的肌节断裂发生在肌节的明带(I带),随着匀浆时间和5℃贮存时间的延长,易碎度也随之增加,PSE肉在前2天的碎化幅度较大,而正常肉在2～4d的碎化幅度较明显。PSE肉与正常肉的肌原纤维易碎度变化规律一致,温度对肌原纤维的碎化效应大于时间效应,且正常肉肌原纤维断裂对温度的敏感性大于PSE肉。由于PSE肉部分肌球蛋白变性,其肌原纤维的舒展肌节长度总是小于正常肉。

The myofibril fragmentation index were compared between normal and PSE pork by determination of their fragmentation,morphology and sarcomere length. Results showed:the fragmentation of sarcomere occurred in I band,the fragmentation index would increase with the increasing of both homogenizing time and storing time at 5℃. The fragmentation of PSE pork was drastically in the first two days,whereas the fragmentation of normal pork was apparent in 2～4 days. The changes of myofibril fragmentation were consistent with which the incubation temperature was more influential than incubation time between normal and PSE pork. The sarcomere of PSE pork was shorter than that of normal pork because of the partial denaturation of PSE myosin.